The present invention relates generally to the field of measuring and testing and more specifically, to the calibration and testing of compasses. Still more specifically, the present invention relates to a mechanism for rotating a compass card which is positioned inside a towed sonar array.
In the past, sonar towed arrays have utilized magnetic compasses to provide an indication of array heading. Such arrays typically comprise a length of PVC tubing which serves as a housing for hydrophone arrays and for several magnetic compasses. The compasses are electrically connected to a monitor system at a remote location where the headings of array modules are displayed. In the past, no method of testing the accuracy of the remote monitor's indication of the array compass heading was possible.